I think the issue is that he was told he was not gong to be a starter. Why else would he clear out the Cardinal pictures from his site. I'm seeing some tweets from football insiders saying that this is a Cardinals/Butler issue not family. Cardinals have kept silent on this.
If that's the case then good riddance. Starting spots are earned, not ordained.
How would he like it if he played the best ball but someone else got the job over him?
I'd be surprised if this is the case though. The Cards still hold his rights. Only an idiot would burn $3.5m and end their career because they don't start game 1. Especially as he was still guaranteed to play 60%+ snaps.